Chain Length and RPMs

Wacomike04

Member
Week 2..... Race 2 ever

So last week we experienced going 13/65 to 13/68 and LOSING rpms, mind you 13/65 was the highest ever @ 6560 rpms. This week I did practice, qualifying, 2 heats, and then a feature. It's a dusty 1/8 mile oval. I did 13/66 practice and qualifying 6230 rpms. I then went to 13/67 first heat 6420 rpms. 13/68 final heat, forgot to reset the rpms, but half lap down. 13/69 the feature 6480 rpms.

So let's get this out so all aspects can be considered. Guy I bought the motor dyno'd it and set it up for his son who is 10 and races plate clones. Guys who ran up front run 13/69-70. I am not perfect, but out of 15 laps in the feature and running high and the apex between the turns, apex of the oval to high on the straights, I HAD TO OF nailed one lap on point. My tach records the top or best rpms until the motor is turned off. I CANNOT get ANYWHERE close to 6800-6900 rpms they say a clone can handle.

My question is....

When this gentleman set up this clone for his son and dyno'd it, set the springs, ect for a restricor plate setup and it just is set up mechanically wrong for a grown man unrestricted? He simply just removed his sons plate and sold it to me the night I bought it. Could my tach be bad? How is a 13/65 the fastest it has done last week? Anything higher in the rear should increase in rpms. But it's like it reverses.....or I put MORE tooth up from there.....then it drops or increases by 50-100 rpms. Like all over the place. But 6550-6600 is top of the hill.

I have a brand.new clone motor for this next weekend which is a two day race. Thinking of just using that. Am I wrong in thinking you can't just dyno this for a 10 year old, remove the restricor plate.....then sell it to a man (360 weight class) I am 390lbs (30 over) as an unrestricted clone and it perform the same? Or should just removing the plate do it and I should be getting 6800 rpms, and my driving sucks? (All 15 laps)

Thanks,
Michael Frizzelle
 
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You cant run a plate motor unrestricted. Cam, springs, carb…everything is different.

Until you get the motor built as an unrestricted, your data is invalid.
 
You cant run a plate motor unrestricted. Cam, springs, carb…everything is different.

Until you get the motor built as an unrestricted, your data is invalid.
Thank you. So the new motor that was built by the same builder.....as an unrestricted clone will outperform this motor dyno'd and set up for this 10 year old by the other guy.

Thank you.
 
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The reason its faster 0n a 13/65 is because thats wher the best hp is .
The mph is connected to the gear ratio/rpm combination .
Axle rpm vs engine rpm .
As stated its not tuned for maximum output at those rpm .
 
Not mentioned was track changes throughout the evening. As the evening moves on, most tracks we see get faster and we have to drop teeth but the rpms stay about the same. Is it possible the track got faster and you were becoming gear bound? Maybe a stopwatch would better tell you than your tach.
 
Week 2..... Race 2 ever

So last week we experienced going 13/65 to 13/68 and LOSING rpms, mind you 13/65 was the highest ever @ 6560 rpms. This week I did practice, qualifying, 2 heats, and then a feature. It's a dusty 1/8 mile oval. I did 13/66 practice and qualifying 6230 rpms. I then went to 13/67 first heat 6420 rpms. 13/68 final heat, forgot to reset the rpms, but half lap down. 13/69 the feature 6480 rpms.

So let's get this out so all aspects can be considered. Guy I bought the motor dyno'd it and set it up for his son who is 10 and races plate clones. Guys who ran up front run 13/69-70. I am not perfect, but out of 15 laps in the feature and running high and the apex between the turns, apex of the oval to high on the straights, I HAD TO OF nailed one lap on point. My tach records the top or best rpms until the motor is turned off. I CANNOT get ANYWHERE close to 6800-6900 rpms they say a clone can handle.

My question is....

When this gentleman set up this clone for his son and dyno'd it, set the springs, ect for a restricor plate setup and it just is set up mechanically wrong for a grown man unrestricted? He simply just removed his sons plate and sold it to me the night I bought it. Could my tach be bad? How is a 13/65 the fastest it has done last week? Anything higher in the rear should increase in rpms. But it's like it reverses.....or I put MORE tooth up from there.....then it drops or increases by 50-100 rpms. Like all over the place. But 6550-6600 is top of the hill.

I have a brand.new clone motor for this next weekend which is a two day race. Thinking of just using that. Am I wrong in thinking you can't just dyno this for a 10 year old, remove the restricor plate.....then sell it to a man (360 weight class) I am 390lbs (30 over) as an unrestricted clone and it perform the same? Or should just removing the plate do it and I should be getting 6800 rpms, and my driving sucks? (All 15 laps)

Thanks,
Michael Frizzelle
In only your 2nd race, unless you have some very special talent, unfortunately this isnt happening. Secondly a restricted clone with just a plate missing isnt going to turn the same RPM an adult clone will turn.
Quit chasing RPM and chase speed and consistency is what you should be going for.
 
In only your 2nd race, unless you have some very special talent, unfortunately this isnt happening. Secondly a restricted clone with just a plate missing isnt going to turn the same RPM an adult clone will turn.
Quit chasing RPM and chase speed and consistency is what you should be going for.
Best advice yet. I keep searching for this 6800 rpms. I ran and hung in the lead pack, and I mean 2 ft away from each other at 13/65 and that 6560. Then I "unexperienced" my way out. Crazy part is.....every "top dog" claims the other top dogs are idiots....and that I should listen to the current one speaking.

It troubles my inner self.....but I'd rather ignore everyone and go sit and figure it out with no stress by myself over a few year time period.

My kids all moved out and I was doing this for FUN, not that being last would be fun, let's not kid ourselves. So I do want to be competitive. But at this point of EVERYONE you are currently standing in front of "know everything".....it's not fun.

Thank you for your response. I see so many leaving the track after running up front talking to their buddies.....drinking a soda.....kicking back. I am going up a tooth, checking my chain tension because it fell off, wondering why my exhaust gasket is only half bolted on....wondering why didn't I see or know to check that after I was sold the motor, and could that gasket half on restrict the exhaust and thus slow down the top end? I am busy from the time I get to the track....to the time I leave.

Exhausting.....
 
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Welcome to the sport!!

I am told golf is as challenging and frustrating as racing.
I cannot see myself playing much golf.

Try to take good notes. Expect to learn something every time out.

Most times suggestions are given as the "rule". Expect exceptions to every rule.


Maintenance will be a big issue. Just remember to finish first, first you must finish.

Keep having fun.
 
make sure your tach is set up to read the correct rpms. raced a limited mod could not find rpms kept going up in gear re set tach to read 10k and was hitting it the entire time. sometimes its something little
 
Welcome to the sport!!

I am told golf is as challenging and frustrating as racing.
I cannot see myself playing much golf.

Try to take good notes. Expect to learn something every time out.

Most times suggestions are given as the "rule". Expect exceptions to every rule.


Maintenance will be a big issue. Just remember to finish first, first you must finish.

Keep having fun.
Golf is so much better, especially if you like to drink.
 
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